Ditch digging machine



March 12, 1957 F. R. HEFT 2,784,506

DITCH DIGGING MACHINE Filed Dec. 8, 1952 5 Sheets-Sheet l T F E H R. F.

DITCH DIGGING MACHINE 3 Sheets-Sheet 2 Filed DeC. 8. 1952.

DITCH DIGGING MACHINE Filed Dec. s, 1952 3 sheets-sheet s 1N V EN TGR.

AUnited States Patent() DITCH DIGGING MACHINE Fred R. Heft, Aitkin,Minn.; Carroll W. Heft, executor of said Fred R. Heft, deceasedApplication December 8, 1952, Serial No. 324,771 4 Claims. (Cl. 257-98)This invention relates to a ditch digging machine and has for itsprincipal objects to provide a machine of this class which is simple,rugged, inexpensive and adapted' for etiicient operation in the diggingof trenches or ditches of various depths.

A particular object is to provide a ditch digging machine'which isadapted to be` drawn by one or more tractors and having novel mechanismunder controlV of an operator riding on the machine for varying thedepth of the trench or ditch for the purpose of compensating forvariations in the ground surface elevation, for maintaining apredetermined slope or gradientat the bottom of the ditch and forprogressively increasing the depth of the excavation. j

A further object is to provide a machine of the class described which isadapted to beoperated to dig ditches or trenches of controlled andvarying depths rapidly.

Another object is to provide a readily portable ditcher having animproved and modified plow-type cutter and moldy board assembly wherebyearth may be excavated to depths of several feet in a step by stepmanner, that is to say, by a succession of passes along the ditch withadjustments to progressively increase the depth of the cut made by eachsucceeding pass.

My invention also includes certain other novel features of constructionwhich will be more fully hereinafter described, including improvementsinthe draft mechanism, depth controlmechanism and means for :stabilizingIthe direction of travel ofthe machine whereby the excavation ofsubstantially straight ditches is facilitated.

The invention will be best understood by reference to `the accompanyingdrawings which illustrate, byY way of example and not for the purpose oflimitation, a preferred form of my invention.

In the drawing:

Figure l is a top plan view of my improved machine;

Fig. 2` is a left elevational View of the same with the left sideground-engaging wheels removed to Show parts otherwise concealed;

Fig. 3 is a somewhat diagrammatic plan view showing a suitablearrangement of draft mechanismand tractors for operating the ditchdigging machine;

Fig. 4 is a side elevational View of the vertically adjustable draftmechanism;

Fig. 5` is a front4 elevational view of the same;

Fig. 6 is a fragmentary cross sectional view through the platformorcatwalk and keel plate;

Fig. 7 isa diagrammatic side elevational view showing atmodification of:the left side supporting wheels, and

Fig` 8 is a vertical cross sectionalview of the machinetakenapproximately on the line 8--8 of Fig.` 1.

Referring to the drawings,` my. improved machine has a,horizontallyelongatedlframe indicated generally byxthe numeral19` and connected tothe front` end` of this `frame is draft mechanism-indicated generally bythe numeral `10. Ground-engaging wheels 11, 12, l3;a,ndll4;are arrangedto supportzthe frame 9. andexcavatingmechanism at various vce elevationsrelative to the surface of the ground being traversed. From the draftmechanism 10, a cutter blade 15 extends obliquely downwardly andrearwardly substantially in a vertical plane and extending incontinuation of this blade I provide a straight vertically disposed keelplate 16 (Figs. 2 and 6). From one side of this plate a platform 17projects horizontally to afford a support in the nature of a catwalk foran operator. This platform is preferably disposed to extend along thebottom of the ditch as it is formed and a seat for the operator may beprovided if considered desirable. p

Projecting from the front end of the platform is an excavator blade 18which delivers the loosened excavated material to an elongated moldboard 19. This mold board is rigidly supported on the frame and extendsobliquely upwardly to the rear and to one side of the excavator blade tocarry material from the bottom of the ditch to the surface of the earthat` various elevations. The mold board 19- has a leading edge portion 20which extends substantially vertically from thev upper edge of the keelplate 16 and a leading. edge portion 21 which converges gradually towarda trailing edge 22 of the mold board. A blade extends along the edge 22`to formi` one side wall of the ditch at a slope of approximately 45 andto allow the excavated material to spill over on the surface of theground at various elevations above the floor of the cut.

A rigid substantially vertical post 23 is located adjacent to the backface of the mold board and the latter is supported` by a: pair ofdiagonal braces 24 extending to the post 23 and by a pair of braces 25which are rigidly connected at their lower ends to the keel plate16.

Mounted` rearwardly of the mold board 19 is a grader blade 26 adapted tospread and remove the excavated material to the outeriside of the trackof the Wheel 12, as indicated in` Fig. 3. One end of the blade 26 isadjustably connected to the post 23 by means of a bracket 27 which maybe secured to the post 23 at any selected elevation. A` rigid arm 28 isadapted to support the outer end portion of theblade26 at an angle ofapproximately 45 relative to the directionv of travel of the machine. To

permit adjustment of Ithe elevation of the grader blade a ball joint 29connects the outer end of the arm 28 to the blade and` a similar jointconnects the inner end of the armr 28 to the machine frame adjacent'tothe keel plate 16. The arm 28 is preferably formed with telescopingmembers and provided with a pin tting in` perforations in these membersto permit adjustment of the effective length` of the arm. The lower edgeof the grader blade 26 extends upon thesurface of the ground andobliquely to the rear of the leading end ofthe blade.

To'support the rear. end of the frame 9 when in traveling position aboveground, a wheel 14 of the caster type is mounted onan arm30 adapted tooscillate about a supporting, substantially vertical pivot 31. Avertical bearing 32 for the pivot 31 has a pivot support 33 on themachine frame andits upperl end portion is connected by atlink 34 to alever 35'thaving a fulcrum support 36. The upper end of the lever 35'isoperatively connected to a nut which isV movable along ascrew shaft 37provided with a manually operable crank 38.r The shaft 37 `is heldagainst longitudinal movement in a bearing 39 so that when the crank 38`is' turnedthe wheel'14 may be raised or lowered relative to the framethrough the linkage described. During the ditchingV opera-tion, thelower periphery of the wheel 141is-raised tolapproximately the elevationof the rear end of the platform 17.'

Arms 11a, 12a and13a connect the wheels 11, 12 and 13 respectively` tothesframek 9, these Wheels being revoluble onaxlesprojectingfrom theouter ends of the severalarms. The inner ends of the arms llatand 12a ij are fxedon oppositeendsof acommonsupporting shaft which extendshorizontally across the machine. A hand wheel 41, disposed within easyreach of an operator standing on the platform 17, is operativelyconnected to the shaft 4t) so that the latter may be forcibly turnedabout its axis through an angle of at least 180. Power transmissionmechanism is interposed between a shaft 42 supporting the hand wheel 41and the shaft 40, the illustrated mechanism including a toothed pinionon the shaft 42 operatively connected by a chain to a sprocket wheel 43,a shaft 44 upon which the wheel 43 is fixed, a worm gear connection in ahousing 45 between shaft 44 and a horizontal shaft and planetary gearingin a housing 46 for transmitting torque to the shaft 40. The arm 13a isfixed on an end of a shaft 47 extending horizontally in suitablebearings on the frame 9 and the shaft 47 is operatively connected to theshaft 40 for rotation in unison therewith by means of suitable sprocketwheels and a chain 48.

The arms 11a and 13a are always in parallel relation one to the other asthey are oscillated about the axes of the shafts 40 and 47 respectivelyand the arms 11a and 12a are retained in a common plane through the axisof the shaft 40 when it is turned. As a result of this construction theoperator, by turning the hand wheel 41, may forcibly raise the frame andexcavating mechanism carried thereby to an elevation above ground or toany selected elevation below the surface of the ground on which thewheels 11, 12 and 13 are supported. The maximum height of the excavatingmechanism is reached when the several arms 11a, 12a and 13a depend fromthe shafts 40 and 47 in vertical planes through the axes of said shaftsrespectively and the lower limit of depth of cut is reached when thearms 11a, 12a and 13a extend upward and outward from the shafts in suchvertical planes.

For most eicient application of the draft power to the front end of themachine frame, I provide the draft mechanism indicated generally by thenumeral 10. By this mechanism, the elevation of the point of applicationof the power is changed to compensate for the changing depth of theexcavating mechanism when in operation at various elevations below theground level. As best shown in Figs. 4 and 5, a rigid bar 50 extendsacross the front of the machine and a pair of perforated lugs 51, one oneach end of the bar 50, project forward from this bar to be connected tocoupling members 52. Parallel side plates 53 have rigidly secured totheir outer surfaces channel bars 54 providing parallel guide flangesfor pairs of rollers S5. The plates 53 are rigidly connected to themachine frame and upper end of the blade 15. The rollers 55 are mountedon brackets 56 fastened to the bar 50 at their front edges so that thedraft bar is guided for movement along the steeply inclined channel bars54. A toothed rack bar 57 is connected at its lower end to the bar 50and its upper end is guided between a toothed pinion 58 and a pair ofrollers 59. A pair of substantially triangular plates 60 confine thesides of the rack bar 57 and carry axial pins for supporting the rollers59. The pinion 53 is fixed on a horizontally extending shaft 61 havingbearings in the side plates 53 and having fixed on one end a sprocketwheel 62 which is operatively connected by a chain 63 to a sprocketwheel 64 fixed on the shaft 4t). By means of this linkage transmittingtorque from the shaft 40 to the shaft 61, the draft bar 5t) isautomatically maintained at an elevation which causes eieientapplication of the draft force at all times. It will be evident that thedraft bar 50 is positioned to the front of the lower end of the guidechannels 54 when the excavating blade 1S is at or near ground level andis positioned directly in front of the upper end portions of the guidechannels 54 when the excavating blade is lowered to its maximum depth inthe ditch.

Projecting forwardly from one of the coupling members 52 is a rigid link65 and a second link 66 is connected to the other coupling member 52 andextends obliquely forward to the link 65 to which it is joined by a pin.

Draft power for moving the machine is applied to the forward end of thelink 65. When a shallow ditch is to be formed by a single pass of themachine and during the rst pass in the operation of cutting deeperditches, a single tractor or other suitable source of power may becoupled to the front end of the link 65. Ordinarily, however, for theexcavation of the deeper ditches two sources of draft power arerequired. For example, as shown in Fig. 3, a pair of crawler typetractors, indicated at 67, may be connected to opposite ends of a rigidcross bar 63 and the ends of this bar may be connected by chains 69 tothe front end of the link 65. The tractors are so operated as to travelin parallel paths land along opposite sides of either a previouslymarked center line along the site of a ditch to be excavated or along apartially excavated ditch 70 which is to be enlarged and increased indepth by successive passes of my improved machine.

Since both the mold board 19 and grader blade 26 under the reactiveforce exerted by the excavated material tend to thrust the machinelaterally toward the opposite or left side, provision is made foropposing and substantially neutralizing this force. In my improvedmachine, lateral or skidding motion is opposed and substantiallyprevented by the Wheels 11 and 13 and the keel plate 16 which penetratesthe ground below the trench bottom and presents a large elongatedvertical surface in sliding engagement with the wall of the trenchopposite to that formed by the mold board.

As indicated in Fig. 7, to further increase the resistance of themachine to lateral skidding motion caused by the mold board and graderblade, an endless type of track or tread 71 may be provided for thesupporting Wheels at one or both sides of the machine. As illustrated,the endless tread 71 is trained on the peripheries of supporting wheels72 and 73 mounted one ahead of the other at a side of the machine, inplace of the wheels 11 and 13. The wheels 72 and 73 may be mounted onthe outer ends of the arms 11a and 13a. The supporting axles of thewheels 72 and 73 may be connected together by a longitudinally extendinglink 74 and the tread 71 formed with longitudinally extending lugsadapted to substantially eliminate lateral skidding motion of themachine due to the reactive forces on the mold board and grader blade.In operation, when the machine is adjusted to travel on a road orsurface of the ground, the excavator blade 18 and keel plate 16 areelevated above the surface of the ground, the several ground engagingwheels are in their lowest positions relative to the frame andexcavating mechanism, and the draft bar 50 is positioned near the lowerends of the guide channels 54. With a suitable source of power coupledto the draft link 65, the machine is readily movable to the site of thetrench or ditch to be formed. At the start of movement along the site ofthe trench an operator stationed on the platform 17 rotates the handWheel 41 in the appropriate direction to raise the wheels 11, 12 and 13relative to the frame thereby lowering the forward end portion of theframe and causing the excavator blade 1S to penetrate the ground. Therear end of the frame and keel plate 16 are also lowered by suitablemanipulation of the crank 38 to raise the wheel 14 to a position whereinits lower periphery is approximately at the elevation of the rear end ofthe platform 17. The tractors or other source or sources of propellingpower are then operated to draw the machine along a predetermined linemarking the center line of the ditch to be dug. Many ground materialsmay be excavated to a depth of from six to twelve inches, depending onthe condition and character of the soil, during a single pass of themachine. Ordinarily, where a ditch of greater depth is required, themachine after being drawn to the end of the shallow ditch formed in onepass is turned around and operated along the ditch in the reversedirection after lowering the excavating asse-soa mechanism to a suitablyincreased depth below the surface.

It will be evident that the soil or material in place is loosened by theblades and 18 and a stream of loosened material is gathered into thelower end of the mold board 19 which conducts such material laterallyand upwardly to the surface of the ground directly in front of thegrader blade 26. This blade operates to spread and convey the materialto the right of the track of the machine so that the excavated materialis out of the way of subsequent operations including the furthertraversing of the machine along the ditch to increase its depth or forother operations such as the laying of pipe or drainage tile in theditch. During the ditching operation, an operator stationed on theplatform 17 adjusts the depth of the cut to compensate forirregularities in the ground level and/or to maintain a predeterminedslope or gradient at the bottom of the ditch. The elongated keel plate16 imparts desirable stability and resistance to lateral deviation froma predetermined line of travel during the ditching operation. Suchlateral deviation is further opposed by my disposition of the wheels 11and 13 and by the endless track 71 and wheels 72 and 73 shown in Fig. 7.

My improved machine, because of its low cost and rugged construction isadapted for use on farms and elsewhere for digging trenches or ditchesfor pipe lines or for drainage ditches either of the open type or forpipes or drainage tile.

Having described my invention, what I claim as new and desire to protectby Letters Patent is:

l. In a ditch digging machine having side and bottom cutters, a singleelongated mold board extending obliquely upward and laterally from oneside of said cutters and a frame rigidly supporting said cutters andmold board, the improvements which comprise, a plurality of wheelsportably supporting said frame, disposed one ahead of the other andspaced laterally from said frame at the side opposite to said moldboard, a third wheel disposed to portably support the opposite side ofthe frame, a support for an operator carried by said frame, meansadapted to be actuated by an operator positioned on said support duringthe ditch digging operation for selectively changing the elevation ofthe frame relative to all of said wheels including means operativelyconnecting said wheels for movement in unison to a multiplicity ofselected common elevations relative to the frame, a vertically disposed,horizontally elongated keel plate adapted to coact with said wheels inmaintaining directional stability to the longitudinal movement of themachine and draft mechanism connected to the front end of said frame.

2. A ditch digging machine in accordance with claim l wherein saidplurality of wheels supporting the frame at the side opposite to themold board are provided with a common endless tread trained on thewheels and affording an elongated ground engaging member.

3. In a ditch digging machine having side and bottom cutters, a singleelongated mold board extending obliquely upward and laterally from oneside of said cutters CII and a frame rigidly supporting said cutters andmold board, the improvements which comprise, wheels portably supportingsaid frame and spaced laterally from said frame at oppositesides-thereof, said wheels including a plurality of wheels disposed oneahead of the other at the side of the frame opposite to the mold board,a support for an operator carried by said frame, elevation control meanscarried by said frame and adapted to be actuated by an operatorpositioned on said support during the ditch digging operation toselectively change the elevation of the frame relative to said wheelsincluding means operatively connecting said wheels together for movementin unison to a multiplicity of selected common elevations relative tothe frame, draft mechanism, means movably connecting said draftmechanism to the front end of said frame, and manually controlled gearmeans disposed to be actuated from a position on said support forpositively and selectively changing the elevation of the draft mechanismeither up or down relative to the frame and for securing the draftmechanism at any of a multiplicity of different elevations on the frameduring the ditch digging operation.

4. In a ditch digging machine having side and bottom cutters, a singleelongated mold board extending obliquely upward and laterally from oneside of said cutters and a frame rigidly supporting said cutters andmold board, the improvements which comprise, wheels portably supportingsaid frame at opposite sides thereof, elevation control means carried bysaid frame and operative to selectively change the elevation of theframe relative to said wheels including means operatively connectingsaid wheels together for movement in unison to selected commonelevations relative to the frame, draft mechanism, draft control meansmovably connecting said draft mechanism to the front end of said frameand operative to selectively change the elevation of the draft mechanismrelative to the frame and means operatively connecting said draftcontrol means to said elevation control means whereby to synchronize theselective changing of the elevation of the frame relative to the wheelswith changes in the elevation of the draft mechanism relative to theframe.

References Cited inthe le of this patent UNITED STATES PATENTS 119,759Hale Oct. 10, 1871 1,271,546 Davison July 9, 1918 1,427,357 Caughey Aug.29, 1922 1,534,900 Bolin Apr. 21, 1925 2,018,138 LeTourneau a Oct. 22,1935 2,158,340 Spieth May 16, 1939 2,195,631 Post et al Apr. 2, 19402,423,544 Acton July 8, 1947 2,437,059 Williams e Mar. 2, 1948 2,595,277Mathias May 6, 1952 FOREIGN PATENTS 24,052 Great Britain Oct. 16, 1897of 1896 t

